The present invention relates to the recovery and/or production of liquid and gaseous hydrocarbons from used scrap tires, and more particularly relates to the processing of scrap tires such that shredding or pulverizing is not required.
A number of processes for the conversion of carbonaceous containing materials into gas and oil for energy consumption have been disclosed. Many of these processes are concerned with the conversion of coal into natural gas and oil products. Also contemplated for conversion are numerous carbonaceous containing waste material, including municipal and industrial waste.
For a more detailed discussion of various processes for the conversion of carbonaceous materials into gaseous fuels, see my co-pending applications, "Apparatus and Method for Producing High Carbon Char, Gaseous Fuels, and Oil from Coal and Like Materials", Ser. No. 548,498, filed Feb. 10, 1975, and "Coal and Carbonaceous Material Converting Process", Ser. No. 573,012, filed Apr. 30, 1975, and both assigned to the same assignee as the present invention. And, disclosed in my co-pending application Ser. No. 558,599, filed Mar. 14, 1975, "Method and Apparatus for Obtaining Hydrocarbons from Rubber Tires and Waste Plastic Materials" is a process for the production of hydrocarbon gas from waste, rubber and plastic materials.
The processes disclosed in my previously filed applications for the conversion of various carbonaceous materials to high energy fuels, are processes which operate at sub-atmospheric pressure, and at relatively low temperatures. In these processes large amounts of volatilization but little chemical reaction takes place, especially since it is in the absence of gaseous reactants such as oxygen. It is believed that by shock heating carbonaceous materials, the hydrocarbons contained therein will volatilize at the interior and displace the liquidized hydrocarbons at the surface. The amount of hydrocarbon gas which can be drawn out of the particles is a function of the gas-solid or solid-liquid interparticle diffusion which occurs. This gaseous diffusion is greatly enhanced by shock heating the particles at sub-atmospheric pressure while mechanically agitating the particles to maximize the surface area through which the gas diffuses.
It is believed that through mechanical agitation and by means of the sub-atmospheric pressure, the diffusing gaseous materials are removed from the carbonaceous particles before they have a chance to repolymerize to more stable, high molecular weight, hydrocarbon solids.
As disclosed in my previously referenced copending application, "Coal and Carbonaceous Materials Converting Process", filed Apr. 30, 1975, Ser. No. 573,012, by burning a portion of the non-volatile component obtained as a by-product of the conversion process, the process may be utilized without resort to an outside energy source. Thus, where there is no requirement for outside energy, the cost of recovering the raw gases and oil is dictated by the cost of the starting material. With respect to scrap materials, such as scrap tires, almost all of the cost is in transporting and feeding the tires into the reaction vessel in a usable form.
The amount of rubber tires discarded as scrap every year in the United States is upward of 3 million tires per year. These scrap tires represent a tremendous source of cheap raw materials for conversion into hydrocarbon gases and oils, which in turn may be utilized as an energy source or as a basic raw material for the production of new rubber and plastic products. Unfortunately, the use of such scrap tires as a source of carbonaceous material has been limited on account of the expense of pre-treating the tires so they can be fed into a conversion process. In the past, such scrap materials have been pre-treated by shredding, pulverizing or by other similar grinding means to render the tire suitable for feeding into a reactor vessel. Compounding the problem with respect to scrap tires, is the wide use of metal reinforcing belts, as well as metal rings around the bead portions of the tires. These non-rubber materials must be removed prior to pulverizing or shredding since if they are not removed, they will result in large build ups of metallic deposits in the rubber conversion processor.
The cost of separating the metal from the nonmetal components of the scrap tire, as well as the cost of pulverizing, shredding or grinding the tires, has made an otherwise ecomically attractive and plentiful raw material commercially prohibitory. It is thus an object of this invention to provide an apparatus and method for feeding scrap tires into a carbonaceous material converting process which does not require the shredding or pulverizing of the tires.
It is another object of this invention to provide a method of feeding metal reinforced tires into a carbonaceous converting process whereby the metal portion of the tire is automatically separated without additional steps.
It is another object of this invention to provide a scrap tire feeding and conversion process which does not require an outside energy source.